1. Technical Field
The present invention relates to a projector, and in particular, to a projector using a solid-state light source.
2. Related Art
A projector is known which includes a single solid-state light source device emitting white light, a color separating and guiding optical system separating light from the single solid-state light source device into a red light component, a green light component, and a blue light component, a light modulation device modulating the respective color light components from the color separating and guiding optical system in accordance with image information, and a projection optical system projecting the modulated light components from the light modulation device as a projection image (for example, see JP-A-2005-274957). According to the projector described in JP-A-2005-274957, the three color light components which are obtained by separating white light emitted from the single solid-state light source device are used as the three color light components (red light component, green light component, and blue light component) which are modulated by the light modulation device. Unlike a projector which includes three solid-state light source devices, the light-emission efficiency (brightness per unit power) or the temperature characteristic (the change of light amount with change in temperature) does not differ between the solid-state light source devices. As a result, the color balance of the projection image can be stabilized.
A projector is also known which includes a solid-state light source device emitting a red light component, a solid-state light source device emitting a green light component, a solid-state light source device emitting a blue light component, a light modulation device modulating the color light components from the respective solid-state light source devices in accordance with image information, and a projection optical system projecting the modulated light components from the light modulation device as a projection image (for example, see JP-A-2002-268140). According to the projector described in JP-A-2002-268140, separate solid-state light source devices (a solid-state light source device emitting a red light component, a solid-state light source device emitting a green light component, and a solid-state light source device emitting a blue light component) are provided for the respective color light components (red light component, green light component, and blue light component), and the three color light components which are respectively emitted from the three solid-state light source devices are used as the three color light components (red light component, green light component, and blue light component) which are modulated by the light modulation device. Thus, the projection image can be brightened compared to a projector which includes a single solid-state light source device.
However, according to the projector described in JP-A-2005-274957, since white light including a red light component, a green light component, and a blue light component is generated from the single solid-state light source device, unlike a projector which includes three solid-state light source devices, a significant thermal load is concentrated on the single solid-state light source device. As a result, it is difficult to further brighten the projection image.
According to the projector described in JP-A-2002-268140, it is difficult to make the three solid-state light source devices respectively emitting the red light component, the green light component, and the blue light component (the solid-state light source device emitting the red light component, the solid-state light source device emitting the green light component, and the solid-state light source device emitting the blue light component) the same light-emission efficiency or temperature characteristic. For this reason, it is difficult to stabilize the color balance of the projection image.